Enable new session crashed bubble UI by Finch experiment.

chrome/browser/ui/startup/startup_browser_creator_impl.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/startup/startup_browser_creator_impl.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "apps/app_restore_service.h"
 #include "apps/app_restore_service_factory.h"
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/environment.h"
 #include "base/lazy_instance.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/statistics_recorder.h"
 #include "base/path_service.h"
 #include "base/prefs/pref_service.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/threading/thread_restrictions.h"
 #include "chrome/browser/apps/install_chrome_app.h"
 #include "chrome/browser/auto_launch_trial.h"
@@ skipping 93 matching lines @@
   LM_WITH_URLS,               // Launched with urls in the cmd line.
   LM_SHORTCUT_NONE,           // Not launched from a shortcut.
   LM_SHORTCUT_NONAME,         // Launched from shortcut but no name available.
   LM_SHORTCUT_UNKNOWN,        // Launched from user-defined shortcut.
   LM_SHORTCUT_QUICKLAUNCH,    // Launched from the quick launch bar.
   LM_SHORTCUT_DESKTOP,        // Launched from a desktop shortcut.
   LM_SHORTCUT_TASKBAR,        // Launched from the taskbar.
   LM_LINUX_MAC_BEOS           // Other OS buckets start here.
 };
 
+// The Finch experiment name and group name that enables new bubble UI after
+// session crashes.
+const char kManagedModeFinchName[] = "EnalbeSessionCrashedBubbleUI";
+const char kEnalbeBubbleUIGroupEnabled[] = "Enabled";
+
 #if defined(OS_WIN)
 // Undocumented flag in the startup info structure tells us what shortcut was
 // used to launch the browser. See http://www.catch22.net/tuts/undoc01 for
 // more information. Confirmed to work on XP, Vista and Win7.
 LaunchMode GetLaunchShortcutKind() {
   STARTUPINFOW si = { sizeof(si) };
   GetStartupInfoW(&si);
   if (si.dwFlags & 0x800) {
     if (!si.lpTitle)
       return LM_SHORTCUT_NONAME;
@@ skipping 696 matching lines @@
   return browser;
 }
 
 void StartupBrowserCreatorImpl::AddInfoBarsIfNecessary(
     Browser* browser,
     chrome::startup::IsProcessStartup is_process_startup) {
   if (!browser || !profile_ || browser->tab_strip_model()->count() == 0)
     return;
 
   if (HasPendingUncleanExit(browser->profile())) {
-    if (!command_line_.HasSwitch(switches::kEnableSessionCrashedBubble) ||
-        !ShowSessionCrashedBubble(browser))
+    // The new bubble UI can be enabled by Finch experiment or by flag.
+    if (!((base::FieldTrialList::FindFullName(kManagedModeFinchName) ==
+               kEnalbeBubbleUIGroupEnabled ||
+           command_line_.HasSwitch(switches::kEnableSessionCrashedBubble)) &&
+          ShowSessionCrashedBubble(browser)))

[Alexei Svitkine (slow), 2014/05/15 19:02:35]

Hmm, I think it would be better to move this logic to
ShowSessionCrashedBubble(), given that we have a single implementation of it.

That way, we won't put users into the active Finch group if they're running a
version of Chrome that doesn't support it.

I think you should also add a --disable flag, so that when the behaviour is
enabled via Finch, one can both turn it on or off explicitly.

(Move both the flag handling and the Finch check into the function.)

[yao, 2014/05/15 21:19:38]

Done.

       SessionCrashedInfoBarDelegate::Create(browser);
   }
 
   // The below info bars are only added to the first profile which is launched.
   // Other profiles might be restoring the browsing sessions asynchronously,
   // so we cannot add the info bars to the focused tabs here.
   if (is_process_startup == chrome::startup::IS_PROCESS_STARTUP &&
       !command_line_.HasSwitch(switches::kTestType)) {
     chrome::ShowBadFlagsPrompt(browser);
     GoogleApiKeysInfoBarDelegate::Create(InfoBarService::FromWebContents(
@@ skipping 73 matching lines @@
       // If the first URL is the NTP, replace it with the sync promo. This
       // behavior is desired because completing or skipping the sync promo
       // causes a redirect to the NTP.
       if (!startup_urls->empty() && IsNewTabURL(profile_, startup_urls->at(0)))
         startup_urls->at(0) = sync_promo_url;
       else
         startup_urls->insert(startup_urls->begin(), sync_promo_url);
     }
   }
 }